Self-cleaning valve



Oct. 28, 1952 E. WOODWARD 2,615,465

SELF-CLEANING VALVE Filed March 21, 1949 2 SHEETS-Sl-IEET 1 Oct. 28,1952 E.WOODWARD 2,615,465

SELF CLEANING VALVE Filed March 21. 1949 2 smi'rs-suss'r 2 Patented Oct.28, 1952 wane -wine 1 x This inventionlrelates .toi-ioutletevalves :of1-.- the type -used to control athhdiseharg exfrom, tanks and the likeand. is "particularly! igoncerneds'iwith an improvedvalveawhichsis.eselfecleaninggand -n; ents;;have been ;madetoieliminatethis leakage and-st1 ingent= regulation l iave .abeeniimposed by @the authoritiesiwith regard toleakager thevalves $1881todaydo not meet. the L requirements. for -1norethanrelativelyshortperiods of timeuwithout 1-,eontinnal =and vfrequenti sexvicing andthe deigners== of ,sl (ah-valvesappearnot. tovhave;v been awa1:e oi themain cause iof:.leakage.

-An oceasional-eauseof leakage isalodgement, of :bglts', nuts=andforeign objects between thevalve and -valve seat. Theseobjectsieanbeiremoved' witli but little troiible lbylmeans. ofoa'ilongflpole and piclc-up attachment. The main vcauseof elealgageresponsiblei01 probably:98%. iofthe leakage, is accumulation of rust or.scale lfrom .the tank-can shell. some of .thisrsealeilodgesu on, .thevalveeseatend .w hen theJvalive-acloses it. presses -ag-ai-nst"the= wetand brittle; seale icrushinglvand impaeting it'intov a. sma1li-mound-,.which sticks; to :iphe valve seatand prlvents: the valve-T from seatm mmma Su'ch moun'ds-of crushed scalexcan occasionally :.:;befiushed;ontbut -.frequently they; adhere. tenacipt 'sly i-to the valvenlseatingisurfaces, and itsis =necessary= to- Jqean the expense. and" loss of;ti'me -incident to;;se nding the; tank .Zcar empty to; the shops-i onremoval of scale arid reconditioning :of

the valve; 'li-l'1is'v occurs long before mautanklcar {Shell -has,esuffici'ent loose scale to warrant steamlain asci aping andaeleaning.

It is,. -tl1 e1 efore, anobject oftthis invention to 5 provideranimproved valve which is; self -c'leaning' and -twhich eliminates the':Iscalei from. theavalve vseats on,-each;opening and? lo'singl of etheivalve.

While;.the;'walve is Y particularly .=.usefu1 when stalled in a tank carhaving a',.shellt,ma de ;of la fenzousgn etal; which. is: subject; .to-.s,,ca 1. Or -rust eformationtit isxalso; suitah1e,,.1. on pth rw s rvce, warms: a ly' he produ dasaiis eae 2 5 and;-inezpensivenesi n iadetediorman 15 to roll foreign objee A.-.f11rt h.e1i iobiectmis to prvidea valv 921 .116- vtype" deseribedlwhivcms of s ch s mp e n nstruc-.tion; that vthe, average mechanic can r adily service it, and toprovide'a valve which- -i s ,orngge d .entjnstallations whetherlarge orsmall. j

sprin reassure; audit V.

the tank, before opemngangl c ifu ztheriobjeets (i v to. provide a s l-sw l ivalve WhiQh.-iS-P%I. a1 se ze neiw tends ,....ve .z,es.andraewsew ipr member. Abutment means on the valve per s ncti n he v l e;tewar l qetesi .-;Q e rite en e ement q i9 afih vem ,pe t l ansttheseatmex her-"att el Q ste silient ine'an d the valve transverselyto the tank car; i Fig. 3 is a horizontal sectional view taken onembodiment; 1

3 usual case the valve stem is advanced downwardly simultaneously withrotation thereof, with a hellcal motion (such as would result from athreaded valve stem support on a valve bonnet or other internallythreaded bushing). In this case it is only after the valve member hascompleted one or more revolutions on its seat (with concomitantcompression of the resilient means and advancement of the valve stem)that the abutment members come into engagement and pcsitively'fo'rce thevalve to its seat or efiecting the final closure of the valve.

It is evident that the invention is not limited to use with valve stemswhich advance toward the valve seat while rotating, and that the valvestem may be actuated in any suitable manner, e. g., successively rotatedand given axial movement. When installed in tank cars, for example, thevalve stem may be actuated by any I of the accepted mechanisms, knownper se, for

moving the vertical valve stem extending through the height of the carand into the dome thereof, such as external handwheels, worm drives,ratchets, etce reference to the accompanying drawings forming a part ofthis specificationand illustrating three specific embodiments thereof byway of illustration. "In the drawing:' v

Fig; 1 is a vertical longitudinal sectional view'of a tank c'arQpartlyinelevation showing-themstallation of the valve; Fig.2 is avertical-sectional view of the valve structure according to'a firstembodiment taken Fig. 4 is avertical sectional view of a second I Fig. 5is a vertlcal sectional view of a third embodiment; and v Figs. 6 and 7are horizontal sectional views taken on lines 6--6'and 'l7 respectively,of Fig. 5'. v

Referring to Figs. 1-3, "the valve may be installed at the bottom of atank Ill, such as the tank of a conventional railroad tank car having a,dome H and locking'ratchet mechanism [2 'comprising a conventionalratchet wheel and a cam or pawl, accessible when'the dome cover isrem'ovedifor locking a valve stem- [3 against rotary motion." The-stemcarries a handwheel I30.

by which the stemmay be-turned to actuate the f valve M. The latter'isdisposed'at the top of a outlet tube l 5 extending out ofthe bottom ofthe tank. I

As is indicated in Fig. 2, the tube [5 has a fvalve seat member I6presenting an annular,up-

wardly directed;bevelled'seating surface. Co-

the val'veseat member. The valvestein guide may 'beformed integrallywith the valve member, or may be formed separately and connected theretoin any suitable manner; in the present specification and claims it isreferred to as a part of the valve member. r

indicatedin Fig.2; It is telescopically mounted .with respect tothevalve stem so as to have limited. relative. .axial movement but totransmit torque by virtue of its "non-circular shape. It

is evident that the valve guide stem H3 or the The invention will bedescribedin detail'by [The valve guide-stem is of non-circular, viz.,

*polygonalshape a rectangular shape having been least one of the stems.

valve stem I3 may be male or female members. In the illustratedembodiment both stems are male members and have rectangularcross-sectional shapes at their near ends. A sleeve I9, which may bemade of one piece, as shown, or of several pieces as indicated in theembodiment shown in Figs. 5 to '7, encloses the ends of the stems and isaxially slidable with respect to at In the instant embodiment the sleeveis slidable with respect to the valve guide stem 18 and secured to thevalve stem by means of bolts 20. The sleeve has rounded edgcs'at thebottom to reduce friction against the valve guide stem 18. Immediatelyabove the sleeve the valve stem is enlarged to provide an externallythreaded portion having threaded engagement with a. bushing 21 supportedby means of supports 22 welded to the tank wall. It will be understoodthat the valve stem is journalled at the top within the ratchetmechanism l2, and that this, together with the bushing 2!, provide meansfor supporting the valve stem and permitting axial and rotary movement.i

The valve member I! is urgedawayfrom the valve stem l3 by means of acoil spring 23 engaging 'an annular groove forming a spring abutment atthe bottom of the sleeve 19 andan abut,- ment 25lat the top of the valvemembeny. Outward movement of the valve member is restrained by ashoulder or lift pin 26 attached to one of the axially movable membersandrunning' in a slot in the other. of these members, it beingunderstood that the stem [Band sleeve 19 are the members referred to.Thus, the pin may be given a drive fit within a transverse hole in theguide stem i3 and run within a vertical slot 21in the side wall of thesleeve. The lower end-of the slot 21 forms a lift pin abutment, limitingthe downward travel of the pin with respect to-the sleeve 19 and actingto lift the pin, and with it, the valve member from its seat when thevalve, stem is retracted. The slot 21 is preferably made wide enough toprevent engagement of the pin 26 with the slot edges'to preventtransmission of torque through the pin, thev torque being preferablytransmitted entirely by the sleeve directly to the guide stem.For-forcing the valve member positively against its seat there areabutments on (i. e., forming a part ofor attached to) the valve stem andvalve member. In the illustrated embodiment the lower end 28 of thevalve stem and the upper end 29 valve member through its guide stem V8,,

. It will be noted from the foregoing construction that the lift pinpreferably transmits neither torque .nor axial thrust toward the valveseat, and that it functions merely .to lift the valve member from itsseat; it is, therefore, subjected to a force only slightly greater thanthat imposed g dependable functionageimea when thefvalve g'uide stein IB fits loosely withinr' the sleeve;- as} shown inthe drawings Upwardtravelof the valve stem 13 may; optionally, be

limited by a stop member 31 secured to theval ve stem to engagethe-bottom 'ofthe bushing2l of the-- spring 23' arepreferably flattened,as

shown; whereby the valve is given a straight downward thrust; thisthrust will not interferewith some free seating. In most installationsit is undes'i'rablet'o have guide vanes or other-strum tnralparts'be'neath the valve member-- l 1 (such, I for'exainple; asthe'va'nes 32 shownin the em sediment according to Figs. 5-7) becausethey hinder the'insertion' of the wooden blocks' w-hi'ch are customarilyinserted into the outletleg: in the caseof' tank cars to absorb thepressure du'e to freezingfor preventing cracking of" the outlet leg whenwater from condensation or other external sources freezes; and becausestructural parts,- extending into the leg, ma-y=pre--- veht' operationof the valve when moistur'e'within -the legf-reezesinto a solid plug.However; the-invention is-applicab1'e' to cases where such guidev'anes'are used;

The operation of the=valve is as follows: The

val-ve being initially clear of its seat, the opera tor m me the-valvestem l3- by means of the wheel l3a; thereby advancing the valvestemthroughthe bushing 2| "toward its seat; all movable partsare-rotating together during this phase, and the pin 26 is at the bottomof the slot 21. When the parts have'beenadvanced to the position shownin Fig; 2. the valve member I! first contacts the valve seat. As. theoperator continues rotation, the spring: 23 is progressively compressedand the valve is rotated on its seat;

simultaneously, the valve stem l3 and sleeve [9' descend,-- causingthe-pin-26 to move upwardly within its slot with respect to the sleeve."If scale has lodged under the valve, thi'srotary movementunder springpressure should be a backward and forward or reciprocatingj movemerit,as "in valve grinding thereby pulverizing scale which will thenwashout.If desiredvalve grinding compound-can be-applied to the valve seat andthe valvereground without removal from the car.

As rotation is continued the abutments 28 and 29 come into engagement,thereby positively forcing the valve member ll'against its seat. Thisinsures solid contact, the force being transmitted from the bushing 2|through the abutments to the valve member and seat member, therebypreventing even hard jars from unseating the valve. The locking ratchetl2 prevents reverse rotation of the stem l3.

When the valve is to be opened the ratchet mechanism 12 is unlatched andthe stem I3 is rotated in the opposite direction; the valve member willrotate while remaining on its seat until the lift pin 26 engages thelift pin abutment, i. e., the bottom of slot 21. Continued rotation willthen lift the valve member from its seat.

The number of revolutions that the valve member makes on its seat underspring tension is determined by the pitch of the threads in the bushing2| in relation to the vertical distance between-the- 'abutrnents 2Braritl-Q'Stwhemthb li ft pin is atthe bottom bisthtnslotr lZi. It.is'zpre-w ferred to provideion one completefrevolutidn 101;? the valvemember underrspringatensiong;but this; may; of 5 course, be varied; es.'g':,. by providing rmlessthan a whole: turn' or: for 'severalzcompleterrevolutions;

inane modified! embodiment; 31mm lag-5.4a,

and abuts a collar 3-3 which limits 1 the upward movement of the valveThe v'alve -accordingwofi this 1 embodiment may be -readily:disassembled! by merely driving out' the pin-- 26 and removingthe'valv'estem I 3 upwa'rdly through the --bushe in'g: 2 l

In. a the: modified embodiment shown-- iniiFlgsa 5-7;? the sleeveiisfarmed intg'ral'ly vvith th" valve stem" I 3 by bifiirc'ating. the endor inestem. SiElcovenplates 35 a'nd 'st are fastened to th e 'bif catedlends oftlfe 'stem; thereby providing hbr of." rectangular' cross-section-ior receivin the'= valve guicle steml8; 'Ih'eslot22T-is; iH-rthiSbodiment, preferablyformed in the side 3 5- "and 3 6 :so' a's nottoweaken the bifurc ofzthe stem l3; which, din-in tli movement ofthevalve; abiit a asurrounding .1 the guide stem wand o'rm'etegrallyvwith-thevalvemember; tlietop-of "e uide stem l8 does not act asan abutment the stem: I B 'm'a'y, therefore, remade-bf lifgh r materialthan in the previous embodiments 1 The spring: 23 =abuts:a'-='sh'oulder' 38 on the part of t "e" valve: stem: 13 below the slotf'I'he valve mem a1 valverstem-vadapted foraxial and rotary motionsfhaving' a non' circul ar-end; ,awalve iriember adapt'ed to engagea seat member -having" annular seating surface and disposed beyond thesaid' end of the valve-stem; a valve--giiide* stem fixed on the-valvemember toward'the valve stem and substantially coaxial therewith, atleast the end of said valve. guide stem being non-circular; a sleeveenclosing said non-circular portions of said stems and having engagementtherewith to transmit torque from the valve stem to the valve guidestem, at least one of said stems being axially slidable within thesleeve to permit axial motion between said stems; resilient means forurging the valve member away from the valve stem; abutment meansoperative to transmit axial thrust from said valve'stem to said valvemember after at least partial compression of said resilient means; andmeans independent of said abutment means for limiting the axial movementof the valve member away from the valve stem, whereby the valve membermay be lifted from the seat member when the valve stem is retracted.

.' 2. The. combination according to claim 1 wherein the other of saidstems is secured .to

toward the interiorqof thevtank; a cooperating valve member having amatching seating surface and a valve guide stem extending away from theseating surface; a valve stem mounted for axial and rotary motions;torque transmitting means connecting the valve stem to the valve guidestem permitting limited axial movement between said stems andtransmitting rotary motion from the valve stem to the ;.valve member,said torque transmitting means comprising a sleeve on one of said stemsfitting telescopically over the other stem with a sliding fit, theengaging surfaces of the; sleeve and said other stem being noncircularin cross-section; resilient means for urgingsaid valve member away fromthe valve stem and toward said, seat member; abutment means on saidvalve stem and valve member positioned to engage each other after atleast partial compression of saidiresilient means subsequent to theseating ofsaidvalve member on the seat member to urge the valve memberpositively against. said seat'member; and means connected between saidvalve stem and valve member for lifting the valve member from its seatafter partial retraction of the valvestem from said seat member. o I

5,1 A- self-cleaning discharge valve for tanks andthe like comprising aseat member at the tank outlet having an annular seating surface facingtoward the interior of the tank; a cooperating valve member having amatching seating surfaceand the valve guide stem extending away from theseating surface; a valve stem mounted for axial and-rotary motions;torque transmitting means connecting the valve stem to the valve guidestem permitting limited axial movement between said stems andtransmitting rotary motion from the valve stem to the valve member,

said torque transmitting means comprising, a.

sleeve on one of the said stems fitting telescopically over the otherstem with a sliding fit, the engaging surfaces of the sleeve and saidother stem b,eing,non circular in cross-section; said sleeve beingseparate from both of said stems having ends of non-circularcross-section; resilient means for urging said valve member away fromthe valve stem and toward said seat member; abutment means on said valvestem and valve member positioned to engage each other after at leastpartial compression of said resilient means subsequent to the seating ofsaid valve member on the seat member to urge the valve member positivelyagainst said seat member; and means connected between said valve stemand valve member for lifting the valve member from its seat afterpartial retraction of the valve stem from said seat member.

6. A self-cleaning discharge valvefortanks and the like comprising aseat member at the tank outlet having an annular seating surface facingtoward the interior of the tank; a cooperating valve member having amatching seating surface and a valve guide stem extending away from theseating surface; a valve stem mounted for axial and rotary motions;torque transmitting means connecting-the valve stem to the valve guidestem permitting limited axial movement between said stems andtransmitting rotary motion from the valve stemto the valve member;resilient means for urging said valve member away from the valve stemand toward said seat member; abutment means formed by the ends of thevalve stem and the valve guide stem engaging each other after at leastpartial compression of said resilient means subsequent to the seating ofsaid valve member on the seat member to urge the valve member positivelyagainst said seat member; and means connected between said valve stemand valve member for lifting the valve member from-its seat afterpartial retraction of the valve stem from'vsaid seat member.

ERWIN WOODWARD."

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number

